package com.github.ulwx.aka.dbutils.tool.support;

/* Copyright 2002-2005 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Base64 {

    /**
     * Specify encoding (value is <code>true</code>).
     */
    public final static boolean ENCODE = true;

    /**
     * Specify decoding (value is <code>false</code>).
     */
    public final static boolean DECODE = false;

    /**
     * Maximum line length (76) of Base64 output.
     */
    private final static int MAX_LINE_LENGTH = 76;

    /**
     * The equals sign (=) as a byte.
     */
    private final static byte EQUALS_SIGN = (byte) '=';

    /**
     * The new line character (\n) as a byte.
     */
    private final static byte NEW_LINE = (byte) '\n';

    /**
     * The 64 valid Base64 values.
     */
    private final static byte[] ALPHABET = {(byte) 'A', (byte) 'B', (byte) 'C',
            (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I',
            (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O',
            (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U',
            (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a',
            (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g',
            (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm',
            (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's',
            (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y',
            (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4',
            (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+',
            (byte) '/'};

    /**
     * Translates a Base64 value to either its 6-bit reconstruction value or a
     * negative number indicating some other meaning.
     **/
    private final static byte[] DECODABET = {-9, -9, -9, -9, -9, -9, -9, -9,
            -9, // Decimal 0 - 8
            -5, -5, // Whitespace: Tab and Linefeed
            -9, -9, // Decimal 11 - 12
            -5, // Whitespace: Carriage Return
            -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 -
            // 26
            -9, -9, -9, -9, -9, // Decimal 27 - 31
            -5, // Whitespace: Space
            -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
            62, // Plus sign at decimal 43
            -9, -9, -9, // Decimal 44 - 46
            63, // Slash at decimal 47
            52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
            -9, -9, -9, // Decimal 58 - 60
            -1, // Equals sign at decimal 61
            -9, -9, -9, // Decimal 62 - 64
            0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through
            // 'N'
            14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O'
            // through 'Z'
            -9, -9, -9, -9, -9, -9, // Decimal 91 - 96
            26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a'
            // through 'm'
            39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n'
            // through 'z'
            -9, -9, -9, -9 // Decimal 123 - 126
            /*
             * ,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 139
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 140 - 152
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 166 - 178
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 205 - 217
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 231 - 243
             * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255
             */
    };

    private final static byte BAD_ENCODING = -9; // Indicates error in encoding
    private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in
    // encoding
    private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in
    // encoding

    /**
     * Defeats instantiation.
     */
    private Base64() {
    }

    /**
     * Testing. Feel free--in fact I encourage you--to throw out this entire
     * "main" method when you actually deploy this code.
     */
    public static void main(String[] args) throws Exception {
        byte[] bytes1 = {(byte) 2, (byte) 2, (byte) 3, (byte) 0, (byte) 9}; // My
        // zip
        // code
        byte[] bytes2 = {(byte) 99, (byte) 2, (byte) 2, (byte) 3, (byte) 0, (byte) 9};
        String s = encodeString("您好。", "gbk");
        System.out.println(s);
        s = Base64.decodeToString(s, "gbk");
        System.out.println(s);

    } // end main

    /* ******** E N C O D I N G M E T H O D S ******** */

    /**
     * Encodes the first three bytes of array <var>threeBytes</var> and returns
     * a four-byte array in Base64 notation.
     *
     * @param threeBytes the array to convert
     * @return four byte array in Base64 notation.
     * @since 1.3
     */
    private static byte[] encode3to4(byte[] threeBytes) {
        return encode3to4(threeBytes, 3);
    } // end encodeToBytes

    /**
     * Encodes up to the first three bytes of array <var>threeBytes</var> and
     * returns a four-byte array in Base64 notation. The actual number of
     * significant bytes in your array is given by <var>numSigBytes</var>. The
     * array <var>threeBytes</var> needs only be as big as
     * <var>numSigBytes</var>.
     *
     * @param threeBytes  the array to convert
     * @param numSigBytes the number of significant bytes in your array
     * @return four byte array in Base64 notation.
     * @since 1.3
     */
    private static byte[] encode3to4(byte[] threeBytes, int numSigBytes) {
        byte[] dest = new byte[4];
        encode3to4(threeBytes, 0, numSigBytes, dest, 0);
        return dest;
    }

    /**
     * Encodes up to three bytes of the array <var>source</var> and writes the
     * resulting four Base64 bytes to <var>destination</var>. The source and
     * destination arrays can be manipulated anywhere along their length by
     * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
     * does not check to make sure your arrays are large enough to accomodate
     * <var>srcOffset</var> + 3 for the <var>source</var> array or
     * <var>destOffset</var> + 4 for the <var>destination</var> array. The
     * actual number of significant bytes in your array is given by
     * <var>numSigBytes</var>.
     *
     * @param source      the array to convert
     * @param srcOffset   the index where conversion begins
     * @param numSigBytes the number of significant bytes in your array
     * @param destination the array to hold the conversion
     * @param destOffset  the index where output will be put
     * @return the <var>destination</var> array
     * @since 1.3
     */
    private static byte[] encode3to4(byte[] source, int srcOffset,
                                     int numSigBytes, byte[] destination, int destOffset) {
        // 1 2 3
        // 01234567890123456789012345678901 Bit position
        // --------000000001111111122222222 Array position from threeBytes
        // --------| || || || | Six bit groups to index ALPHABET
        // >>18 >>12 >> 6 >> 0 Right shift necessary
        // 0x3f 0x3f 0x3f Additional AND

        // Create buffer with zero-padding if there are only one or two
        // significant bytes passed in the array.
        // We have to shift left 24 in order to flush out the 1's that appear
        // when Java treats a value as negative that is cast from a byte to an
        // int.
        int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
                | (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
                | (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);

        switch (numSigBytes) {
            case 3:
                destination[destOffset] = ALPHABET[(inBuff >>> 18)];
                destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
                destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
                destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f];
                return destination;

            case 2:
                destination[destOffset] = ALPHABET[(inBuff >>> 18)];
                destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
                destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
                destination[destOffset + 3] = EQUALS_SIGN;
                return destination;

            case 1:
                destination[destOffset] = ALPHABET[(inBuff >>> 18)];
                destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
                destination[destOffset + 2] = EQUALS_SIGN;
                destination[destOffset + 3] = EQUALS_SIGN;
                return destination;

            default:
                return destination;
        } // end switch
    } // end encode3to4

    /**
     * Serializes an object and returns the Base64-encoded version of that
     * serialized object. If the object cannot be serialized or there is another
     * error, the method will return <code>null</code>.
     *
     * @param serializableObject The object to encode
     * @return The Base64-encoded object
     * @since 1.4
     */
    public static String encodeObject(java.io.Serializable serializableObject) {
        return encodeObject(serializableObject, true);
    } // end encodeObject

    /**
     * Serializes an object and returns the Base64-encoded version of that
     * serialized object. If the object cannot be serialized or there is another
     * error, the method will return <code>null</code>.
     *
     * @param serializableObject The object to encode
     * @param breakLines         Break lines at 80 characters or less.
     * @return The Base64-encoded object
     * @since 1.4
     */
    public static String encodeObject(java.io.Serializable serializableObject,
                                      boolean breakLines) {
        java.io.ByteArrayOutputStream baos = null;
        java.io.OutputStream b64os = null;
        java.io.ObjectOutputStream oos = null;

        try {
            baos = new java.io.ByteArrayOutputStream();
            b64os = new OutputStream(baos, Base64.ENCODE, breakLines);
            oos = new java.io.ObjectOutputStream(b64os);

            oos.writeObject(serializableObject);
        } // end try
        catch (java.io.IOException e) {
            e.printStackTrace();
            return null;
        } // end catch
        finally {
            try {
                oos.close();
            } catch (Exception e) {
                // ignore it
            }
            try {
                b64os.close();
            } catch (Exception e) {
                // ignore it
            }
            try {
                baos.close();
            } catch (Exception e) {
                // ignore it
            }
        } // end finally

        return new String(baos.toByteArray());
    } // end encode

    /**
     * Encodes a byte array into Base64 notation. Equivalen to calling
     * <code>encodeBytes( source, 0, source.length )</code>
     *
     * @param source The data to convert
     * @since 1.4
     */
    public static String encodeBytes(byte[] source) throws Exception {
        return encodeBytes(source, true);
    } // end encodeBytes

    /**
     * Encodes a byte array into Base64 notation. Equivalen to calling
     * <code>encodeBytes( source, 0, source.length )</code>
     *
     * @param source     The data to convert
     * @param breakLines Break lines at 80 characters or less.
     * @since 1.4
     */
    private static String encodeBytes(byte[] source, boolean breakLines)
            throws Exception {
        return encodeBytes(source, 0, source.length, breakLines);
    } // end encodeBytes

    /**
     * Encodes a byte array into Base64 notation.
     *
     * @param source The data to convert
     * @param off    Offset in array where conversion should begin
     * @param len    Length of data to convert
     * @since 1.4
     */
    public static String encodeBytes(byte[] source, int off, int len)
            throws Exception {
        return encodeBytes(source, off, len, true);
    } // end encodeBytes

    /**
     * Encodes a byte array into Base64 notation.
     *
     * @param source     The data to convert
     * @param off        Offset in array where conversion should begin
     * @param len        Length of data to convert
     * @param breakLines Break lines at 80 characters or less.
     * @since 1.4
     */
    public static String encodeBytes(byte[] source, int off, int len,
                                     boolean breakLines) throws Exception {
        int len43 = len * 4 / 3;
        byte[] outBuff = new byte[(len43) // Main 4:3
                + ((len % 3) > 0 ? 4 : 0) // Account for padding
                + (breakLines ? (len43 / MAX_LINE_LENGTH) : 0)]; // New lines
        int d = 0;
        int e = 0;
        int len2 = len - 2;
        int lineLength = 0;
        for (; d < len2; d += 3, e += 4) {
            encode3to4(source, d + off, 3, outBuff, e);

            lineLength += 4;
            if (breakLines && lineLength == MAX_LINE_LENGTH) {
                outBuff[e + 4] = NEW_LINE;
                e++;
                lineLength = 0;
            } // end if: end of line
        } // en dfor: each piece of array

        if (d < len) {
            encode3to4(source, d + off, len - d, outBuff, e);
            e += 4;
        } // end if: some padding needed

        return new String(outBuff, 0, e, "iso-8859-1");
    } // end encodeBytes

    /**
     * Encodes a string in Base64 notation with line breaks after every 75
     * Base64 characters.
     *
     * @param s the string to encode
     * @return the encoded string
     * @since 1.3
     */
    public static String encodeString(String s, String charset)
            throws Exception {
        return encodeString(s, true, charset);
    } // end encodeString

    /**
     * Encodes a string in Base64 notation with line breaks after every 75
     * Base64 characters.
     *
     * @param s          the string to encode
     * @param breakLines Break lines at 80 characters or less.
     * @return the encoded string
     * @since 1.3
     */
    private static String encodeString(String s, boolean breakLines,
                                       String charset) throws Exception {
        return encodeBytes(s.getBytes(charset), breakLines);
    } // end encodeString

    /* ******** D E C O D I N G M E T H O D S ******** */

    /**
     * Decodes the first four bytes of array <var>fourBytes</var> and returns an
     * array up to three bytes long with the decoded values.
     *
     * @param fourBytes the array with Base64 content
     * @return array with decoded values
     * @since 1.3
     */
    private static byte[] decode4to3(byte[] fourBytes) {
        byte[] outBuff1 = new byte[3];
        int count = decode4to3(fourBytes, 0, outBuff1, 0);
        byte[] outBuff2 = new byte[count];

        System.arraycopy(outBuff1, 0, outBuff2, 0, count);
        return outBuff2;
    }

    /**
     * Decodes four bytes from array <var>source</var> and writes the resulting
     * bytes (up to three of them) to <var>destination</var>. The source and
     * destination arrays can be manipulated anywhere along their length by
     * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
     * does not check to make sure your arrays are large enough to accomodate
     * <var>srcOffset</var> + 4 for the <var>source</var> array or
     * <var>destOffset</var> + 3 for the <var>destination</var> array. This
     * method returns the actual number of bytes that were converted from the
     * Base64 encoding.
     *
     * @param source      the array to convert
     * @param srcOffset   the index where conversion begins
     * @param destination the array to hold the conversion
     * @param destOffset  the index where output will be put
     * @return the number of decoded bytes converted
     * @since 1.3
     */
    private static int decode4to3(byte[] source, int srcOffset,
                                  byte[] destination, int destOffset) {
        // Example: Dk==
        if (source[srcOffset + 2] == EQUALS_SIGN) {
            // Two ways to do the same thing. Don't know which way I like best.
            // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6
            // )
            // | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
            int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
                    | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);

            destination[destOffset] = (byte) (outBuff >>> 16);
            return 1;
        }

        // Example: DkL=
        else if (source[srcOffset + 3] == EQUALS_SIGN) {
            // Two ways to do the same thing. Don't know which way I like best.
            // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6
            // )
            // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
            // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
            int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
                    | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
                    | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);

            destination[destOffset] = (byte) (outBuff >>> 16);
            destination[destOffset + 1] = (byte) (outBuff >>> 8);
            return 2;
        }

        // Example: DkLE
        else {
            try {
                // Two ways to do the same thing. Don't know which way I like
                // best.
                // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 )
                // >>> 6 )
                // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
                // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
                // | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
                int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
                        | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
                        | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6)
                        | ((DECODABET[source[srcOffset + 3]] & 0xFF));

                destination[destOffset] = (byte) (outBuff >> 16);
                destination[destOffset + 1] = (byte) (outBuff >> 8);
                destination[destOffset + 2] = (byte) (outBuff);

                return 3;
            } catch (Exception e) {

                return -1;
            } // end catch
        }
    } // end decodeToBytes

    /**
     * Decodes data from Base64 notation.
     *
     * @param s the string to decode
     * @return the decoded data
     * @since 1.4
     */
    public static byte[] decode(String s) throws Exception {
        byte[] bytes = s.getBytes("iso-8859-1");
        return decode(bytes, 0, bytes.length);
    } // end decode

    /**
     * Decodes data from Base64 notation and returns it as a string. Equivlaent
     * to calling <code>new String( decode( s ) )</code>
     *
     * @param s the strind to decode
     * @return The data as a string
     * @since 1.4
     */
    public static String decodeToString(String s, String charset)
            throws Exception {
        return new String(decode(s), charset);
    } // end decodeToString

    /**
     * Attempts to decode Base64 data and deserialize a Java Object within.
     * Returns <code>null</code> if there was an error.
     *
     * @param encodedObject The Base64 data to decode
     * @return The decoded and deserialized object
     * @since 1.4
     */
    public static Object decodeToObject(String encodedObject) throws Exception {
        byte[] objBytes = decode(encodedObject);

        java.io.ByteArrayInputStream bais = null;
        java.io.ObjectInputStream ois = null;

        try {
            bais = new java.io.ByteArrayInputStream(objBytes);
            ois = new java.io.ObjectInputStream(bais);

            return ois.readObject();
        } // end try
        catch (java.io.IOException e) {
            e.printStackTrace();
            return null;
        } // end catch
        catch (ClassNotFoundException e) {
            e.printStackTrace();
            return null;
        } // end catch
        finally {
            try {
                bais.close();
            } catch (Exception e) {
                // ignore it
            }
            try {
                ois.close();
            } catch (Exception e) {
                // ignore it
            }
        } // end finally
    } // end decodeObject

    /**
     * Decodes Base64 content in byte array format and returns the decoded byte
     * array.
     *
     * @param source The Base64 encoded data
     * @param off    The offset of where to begin decoding
     * @param len    The length of characters to decode
     * @return decoded data
     * @since 1.3
     */
    private static byte[] decode(byte[] source, int off, int len) {
        int len34 = len * 3 / 4;
        byte[] outBuff = new byte[len34]; // Upper limit on size of output
        int outBuffPosn = 0;

        byte[] b4 = new byte[4];
        int b4Posn = 0;
        int i = 0;
        byte sbiCrop = 0;
        byte sbiDecode = 0;
        for (i = 0; i < len; i++) {
            sbiCrop = (byte) (source[i] & 0x7f); // Only the low seven bits
            sbiDecode = DECODABET[sbiCrop];

            if (sbiDecode >= WHITE_SPACE_ENC) // White space, Equals sign or
            // better
            {
                if (sbiDecode >= EQUALS_SIGN_ENC) {
                    b4[b4Posn++] = sbiCrop;
                    if (b4Posn > 3) {
                        outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn);
                        b4Posn = 0;

                        // If that was the equals sign, break out of 'for' loop
                        if (sbiCrop == EQUALS_SIGN)
                            break;
                    } // end if: quartet built

                } // end if: equals sign or better

            } // end if: white space, equals sign or better
            else {
                return null;
            } // end else:
        } // each input character

        byte[] out = new byte[outBuffPosn];
        System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
        return out;
    } // end decode

    /* ******** I N N E R C L A S S I N P U T S T R E A M ******** */

    /**
     * A {@link InputStream} will read data from another
     * {@link java.io.InputStream}, given in the constructor, and encode/decode
     * to/from Base64 notation on the fly.
     *
     * @see Base64
     * @see java.io.FilterInputStream
     * @since 1.3
     */
    public static class InputStream extends java.io.FilterInputStream {
        private boolean encode; // Encoding or decoding
        private int position; // Current position in the buffer
        private byte[] buffer; // Small buffer holding converted data
        private int bufferLength; // Length of buffer (3 or 4)
        private int numSigBytes; // Number of meaningful bytes in the buffer
        private int lineLength;
        private boolean breakLines; // Break lines at less than 80 characters

        /**
         * Constructs a {@link InputStream} in DECODE mode.
         *
         * @param in the {@link java.io.InputStream} from which to read data.
         * @since 1.3
         */
        public InputStream(java.io.InputStream in) {
            this(in, Base64.DECODE);
        } // end constructor

        /**
         * Constructs a {@link InputStream} in either ENCODE or DECODE
         * mode.
         *
         * @param in     the {@link java.io.InputStream} from which to read data.
         * @param encode Conversion direction
         * @see Base64#ENCODE
         * @see Base64#DECODE
         * @since 1.3
         */
        public InputStream(java.io.InputStream in, boolean encode) {
            this(in, encode, true);
        } // end constructor

        /**
         * Constructs a {@link InputStream} in either ENCODE or DECODE
         * mode.
         *
         * @param in         the {@link java.io.InputStream} from which to read data.
         * @param encode     Conversion direction
         * @param breakLines Break lines at less than 80 characters.
         * @see Base64#ENCODE
         * @see Base64#DECODE
         * @since 1.3
         */
        public InputStream(java.io.InputStream in, boolean encode,
                           boolean breakLines) {
            super(in);
            this.breakLines = breakLines;
            this.encode = encode;
            this.bufferLength = encode ? 4 : 3;
            this.buffer = new byte[bufferLength];
            this.position = -1;
            this.lineLength = 0;
        } // end constructor

        /**
         * Reads enough of the input stream to convert to/from Base64 and
         * returns the next byte.
         *
         * @return next byte
         * @since 1.3
         */
        public int read() throws java.io.IOException {
            // Do we need to get data?
            if (position < 0) {
                if (encode) {
                    byte[] b3 = new byte[3];
                    int numBinaryBytes = 0;
                    for (int i = 0; i < 3; i++) {
                        try {
                            int b = in.read();

                            // If end of stream, b is -1.
                            if (b >= 0) {
                                b3[i] = (byte) b;
                                numBinaryBytes++;
                            } // end if: not end of stream

                        } // end try: read
                        catch (java.io.IOException e) {
                            // Only a problem if we got no data at all.
                            if (i == 0)
                                throw e;

                        } // end catch
                    } // end for: each needed input byte

                    if (numBinaryBytes > 0) {
                        encode3to4(b3, 0, numBinaryBytes, buffer, 0);
                        position = 0;
                        numSigBytes = 4;
                    } // end if: got data
                    else {
                        return -1;
                    } // end else
                } // end if: encoding

                // Else decoding
                else {
                    byte[] b4 = new byte[4];
                    int i = 0;
                    for (i = 0; i < 4; i++) {
                        // Read four "meaningful" bytes:
                        int b = 0;
                        do {
                            b = in.read();
                        } while (b >= 0
                                && DECODABET[b & 0x7f] <= WHITE_SPACE_ENC);

                        if (b < 0)
                            break; // Reads a -1 if end of stream

                        b4[i] = (byte) b;
                    } // end for: each needed input byte

                    if (i == 4) {
                        numSigBytes = decode4to3(b4, 0, buffer, 0);
                        position = 0;
                    } // end if: got four characters
                    else if (i == 0) {
                        return -1;
                    } // end else if: also padded correctly
                    else {
                        // Must have broken out from above.
                        throw new java.io.IOException(
                                "Improperly padded Base64 input.");
                    } // end

                } // end else: decode
            } // end else: get data

            // Got data?
            if (position >= 0) {
                // End of relevant data?
                if ( /* !encode && */position >= numSigBytes)
                    return -1;

                if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) {
                    lineLength = 0;
                    return '\n';
                } // end if
                else {
                    lineLength++; // This isn't important when decoding
                    // but throwing an extra "if" seems
                    // just as wasteful.

                    int b = buffer[position++];

                    if (position >= bufferLength)
                        position = -1;

                    return b & 0xFF; // This is how you "cast" a byte that's
                    // intended to be unsigned.
                } // end else
            } // end if: position >= 0

            // Else error
            else {
                // When JDK1.4 is more accepted, use an assertion here.
                throw new java.io.IOException(
                        "Error in Base64 code reading stream.");
            } // end else
        } // end read

        /**
         * Calls {@link #read} repeatedly until the end of stream is reached or
         * <var>len</var> bytes are read. Returns number of bytes read into
         * array or -1 if end of stream is encountered.
         *
         * @param dest array to hold values
         * @param off  offset for array
         * @param len  max number of bytes to read into array
         * @return bytes read into array or -1 if end of stream is encountered.
         * @since 1.3
         */
        public int read(byte[] dest, int off, int len)
                throws java.io.IOException {
            int i;
            int b;
            for (i = 0; i < len; i++) {
                b = read();

                // if( b < 0 && i == 0 )
                // return -1;

                if (b >= 0)
                    dest[off + i] = (byte) b;
                else if (i == 0)
                    return -1;
                else
                    break; // Out of 'for' loop
            } // end for: each byte read
            return i;
        } // end read

    } // end inner class InputStream

    /* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */

    /**
     * A {@link OutputStream} will write data to another
     * {@link java.io.OutputStream}, given in the constructor, and encode/decode
     * to/from Base64 notation on the fly.
     *
     * @see Base64
     * @see java.io.FilterOutputStream
     * @since 1.3
     */
    public static class OutputStream extends java.io.FilterOutputStream {
        private boolean encode;
        private int position;
        private byte[] buffer;
        private int bufferLength;
        private int lineLength;
        private boolean breakLines;

        /**
         * Constructs a {@link OutputStream} in ENCODE mode.
         *
         * @param out the {@link java.io.OutputStream} to which data will be
         *            written.
         * @since 1.3
         */
        public OutputStream(java.io.OutputStream out) {
            this(out, Base64.ENCODE);
        } // end constructor

        /**
         * Constructs a {@link OutputStream} in either ENCODE or DECODE
         * mode.
         *
         * @param out    the {@link java.io.OutputStream} to which data will be
         *               written.
         * @param encode Conversion direction
         * @see Base64#ENCODE
         * @see Base64#DECODE
         * @since 1.3
         */
        public OutputStream(java.io.OutputStream out, boolean encode) {
            this(out, encode, true);
        } // end constructor

        /**
         * Constructs a {@link OutputStream} in either ENCODE or DECODE
         * mode.
         *
         * @param out        the {@link java.io.OutputStream} to which data will be
         *                   written.
         * @param encode     Conversion direction
         * @param breakLines Break lines to be less than 80 characters.
         * @see Base64#ENCODE
         * @see Base64#DECODE
         * @since 1.3
         */
        public OutputStream(java.io.OutputStream out, boolean encode,
                            boolean breakLines) {
            super(out);
            this.breakLines = breakLines;
            this.encode = encode;
            this.bufferLength = encode ? 3 : 4;
            this.buffer = new byte[bufferLength];
            this.position = 0;
            this.lineLength = 0;
        } // end constructor

        /**
         * Writes the byte to the output stream after converting to/from Base64
         * notation. When encoding, bytes are buffered three at a time before
         * the output stream actually gets a write() call. When decoding, bytes
         * are buffered four at a time.
         *
         * @param theByte the byte to write
         * @since 1.3
         */
        public void write(int theByte) throws java.io.IOException {
            if (encode) {
                buffer[position++] = (byte) theByte;
                if (position >= bufferLength) // Enough to encode.
                {
                    out.write(Base64.encode3to4(buffer, bufferLength));

                    lineLength += 4;
                    if (breakLines && lineLength >= MAX_LINE_LENGTH) {
                        out.write(NEW_LINE);
                        lineLength = 0;
                    } // end if: end of line

                    position = 0;
                } // end if: enough to output
            } // end if: encoding

            // Else, Decoding
            else {
                // Meaningful Base64 character?
                if (DECODABET[theByte & 0x7f] > WHITE_SPACE_ENC) {
                    buffer[position++] = (byte) theByte;
                    if (position >= bufferLength) // Enough to output.
                    {
                        out.write(Base64.decode4to3(buffer));
                        position = 0;
                    } // end if: enough to output
                } // end if: meaningful Base64 character
                else if (DECODABET[theByte & 0x7f] != WHITE_SPACE_ENC) {
                    throw new java.io.IOException(
                            "Invalid character in Base64 data.");
                } // end else: not white space either
            } // end else: decoding
        } // end write

        /**
         * Calls {@link #write} repeatedly until <var>len</var> bytes are
         * written.
         *
         * @param theBytes array from which to read bytes
         * @param off      offset for array
         * @param len      max number of bytes to read into array
         * @since 1.3
         */
        public void write(byte[] theBytes, int off, int len)
                throws java.io.IOException {
            for (int i = 0; i < len; i++) {
                write(theBytes[off + i]);
            } // end for: each byte written

        } // end write

        /**
         * Appropriately pads Base64 notation when encoding or throws an
         * exception if Base64 input is not properly padded when decoding.
         *
         * @since 1.3
         */
        public void flush() throws java.io.IOException {
            super.flush();

            if (position > 0) {
                if (encode) {
                    out.write(Base64.encode3to4(buffer, position));
                } // end if: encoding
                else {
                    throw new java.io.IOException(
                            "Base64 input not properly padded.");
                } // end else: decoding
            } // end if: buffer partially full

            out.flush();
        } // end flush

        /**
         * Flushes and closes stream.
         *
         * @since 1.3
         */
        public void close() throws java.io.IOException {
            super.close();
            // this.flush();

            out.close();

            buffer = null;
            out = null;
        } // end close

    } // end inner class OutputStream

} // end class Base64
